work, copies of the plans and specifications must be filed at a central ofiice, and be approved by some competent person; that the work as it progresses, or when completed, must be inspected by a municipal officer, and that there shall be a register of those plumbers who are considered competent to do such work.
Usually also there is provision for the inspection of the plumbing of any house when there is reason to suspect that it is in a dangerous condition, or upon the application of the owner or tenant. It is common to require the ventilation of soil-pipes and traps, the trap between the sewer and the house, and the fresh-air inlet, and that all soil-pipes within the house, whether vertical or horizontal, shall be of iron. These regulations are not approved by certain manufacturers and patentees, who find that they conflict with their interests; but upon the whole it is best to allow the municipal health authorities to settle these questions, rather than to have them controlled by trade interests, and it is better to have the rules uniform, and leave as little as possible to the discretion of the officials, even though, in a few cases, this may lead to the putting in of a trap or ventilating-pipe which is not absolutely essential.
The first municipal Board of Health to carefully investigate the subject of defective house-drainage, and to issue instructions and regulations with regard to it, was the Metropolitan Board of Health of New York city under the presidency of Prof. C. F. Chandler, of Columbia College, from 1875 to 1883. To meet the requirements of the board, manufacturers rapidly produced new and improved forms of fixtures, a registration of plumbers was established by law, and the rules and regulations of New York city have practically been the model for those of other cities.
There is still another point of view to which brief reference may be made, viz., that of a man who has a pecuniary interest in certain forms of apparatus, closets, traps, etc., which he wishes to have introduced as extensively as possible. He does not approve of municipal or other regulations which make the use of his appliances difficult or expensive, and he will look favorably on those rules which require the use of his apparatus or its equivalent. It is not to be expected that he will advocate the use of new forms of apparatus, unless, indeed, he owns the patent for them, or has introduced them himself; yet this does not necessarily follow, and still less is it to be assumed that, because a man seeks to promote his pecuniary interests, his arguments and propositions are necessarily unsound, and to be condemned.
Professional men, such as physicians, architects, and engineers, do not, as a rule, look favorably upon the taking out of patents connected with their special work. This is formulated in the code of ethics ofin the statement that "it is derogatory